<!-- this page copy from https://blog.ltyuanfang.cn/shizhong -->
<template>
  <div class="fill">
    <div class="reference"></div>
    <div class="clock" id="utility-clock">
      <div class="centre">
        <div class="dynamic"></div>
        <div class="expand round circle-1"></div>
        <div class="anchor hour">
          <div class="element thin-hand"></div>
          <div class="element fat-hand"></div>
        </div>
        <div class="anchor minute">
          <div class="element thin-hand"></div>
          <div class="element fat-hand minute-hand"></div>
        </div>
        <div class="anchor second">
          <div class="element second-hand"></div>
        </div>
        <div class="expand round circle-2"></div>
        <div class="expand round circle-3"></div>
      </div>
    </div>
  </div>
</template>

<script setup>
import { onMounted } from 'vue';

onMounted(() => {
  // 在这里可以安全地使用 document 对象
  const clock = document.querySelector('#utility-clock');
  utilityClock(clock)

  if (clock.parentNode.classList.contains('fill')) autoResize(clock, 295 + 32)
})

function utilityClock(container) {
  let i;
  const rotate = function(element, second) {
    element.style.transform = element.style.webkitTransform = 'rotate(' + (second * 6) + 'deg)'
  };
  const position = function(element, phase, r) {
    const theta = phase * 2 * Math.PI;
    element.style.top = (-r * Math.cos(theta)).toFixed(1) + 'px'
    element.style.left = (r * Math.sin(theta)).toFixed(1) + 'px'
  };
  const minuteLine = function(n) {
    const anchor = document.createElement('div');
    anchor.className = 'anchor'
    const element = document.createElement('div');
    element.className = 'element minute-line'
    rotate(anchor, n)
    anchor.appendChild(element)
    dynamic.appendChild(anchor)
  };
  const minuteText = function(n) {
    const element = document.createElement('div');
    element.className = 'minute-text'
    element.innerHTML = (n < 10 ? '0' : '') + n
    position(element, n / 60, 135)
    dynamic.appendChild(element)
  };
  const dynamic = container.querySelector('.dynamic');
  const hourElement = container.querySelector('.hour');
  const minuteElement = container.querySelector('.minute');
  const secondElement = container.querySelector('.second');
  const minute = function (n) {
    return n % 5 == 0 ? minuteText(n) : minuteLine(n)
  };
  const hour = function (n) {
    const element = document.createElement('div');
    element.className = 'hour-text hour-' + n
    element.innerHTML = n
    position(element, n / 12, 105)
    dynamic.appendChild(element)
  };
  const animate = function () {
    const now = new Date();
    const time = now.getHours() * 3600 +
        now.getMinutes() * 60 +
        now.getSeconds() * 1 +
        now.getMilliseconds() / 1000;
    rotate(secondElement, time)
    rotate(minuteElement, time / 60)
    rotate(hourElement, time / 60 / 12)
    requestAnimationFrame(animate)
  };
  for (i = 1; i <= 60; i ++) minute(i)
  for (i = 1; i <= 12; i ++) hour(i)
  animate()
}

function autoResize(element, nativeSize) {
  const update = function () {
    const scale = Math.min(window.innerWidth, window.innerHeight) / nativeSize;
    element.style.transform = element.style.webkitTransform = 'scale(' + scale.toFixed(3) + ')'
  };
  update()
  window.addEventListener('resize', update)
}
</script>

<style>
.clock {
  position: absolute;
  opacity: 1;
}

.fill .clock {
  left: 50%;
  top: 50%;
}

.centre {
  position: absolute;
  top: 50%;
  left: 50%;
  width: 0;
  height: 0;
}

.expand {
  position: absolute;
  top: 0;
  left: 0;
  transform: translate(-50%, -50%);
}

.anchor {
  position: absolute;
  top: 0;
  left: 0;
  width: 0;
  height: 0;
}

.element {
  position: absolute;
  top: 0;
  left: 0;
}

.round {
  border-radius: 296px;
}

.circle-1 {
  background: white;
  width: 12px;
  height: 12px;
}

.circle-2 {
  background: #FA9F22;
  width: 8px;
  height: 8px;
}

.circle-3 {
  background: black;
  width: 4px;
  height: 4px;
}

.second {
  transform: rotate(180deg);
}

.minute {
  transform: rotate(54deg);
}

.second-hand {
  width: 2px;
  height: 164px;
  background: #FA9F22;
  transform: translate(-50%,-100%) translateY(24px);
}

.hour {
  transform: rotate(304.5deg);
}

.thin-hand {
  width: 4px;
  height: 50px;
  background: #7f7f7f;
  transform: translate(-50%,-100%);
}

.fat-hand {
  width: 10px;
  height: 57px;
  border-radius: 10px;
  background: #7f7f7f;
  transform: translate(-50%,-100%) translateY(-18px);
}

.minute-hand {
  height: 112px;
}

.hour-text {
  position: absolute;
  font: 40px Hei, Helvetica, Arial, sans-serif;
  color: #7f7f7f;
  transform: translate(-50%,-50%);
}

.hour-10 {
  padding-left: 0.4ex;
}
.hour-11 {
  padding-left: 0.25ex;
}

.minute-text {
  position: absolute;
  font: 12px Avenir Next, Helvetica, Arial, sans-serif;
  color: #7f7f7f;
  transform: translate(-50%,-50%);
}

.minute-line {
  background: #7f7f7f;
  width: 1px;
  height: 9px;
  transform: translate(-50%,-100%) translateY(-131px);
  opacity: 1;
  /*opacity: 0.34;*/
}
</style>


